What is a default constraint in SQL?
What is a default constraint in SQL?
#constraints #sqltutorialforbeginners #databasemanagement
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Chapters:
00:00 Introduction
00:06 What is Default Constraint
00:11 Explanation of Default Constraint
00:34 Practical Example of Default Constraint
00:55 Defining Default Values in SQL
01:26 Wrap Up and Next Steps
01:31 Conclusion and Call to Action
Hello everyone, welcome to Educate Cube. Today we will learn about what a default constraint is. So, what is a default constraint? It is used to specify a default value for a column so that when no explicit value is provided during an insert operation, a default value is used.
For instance, if data is ingested and by chance, some data is missing, we would like to automatically assign a value. For example, if someone’s initials are not provided, like Mr. or Mrs., and nothing is mentioned, we can specify that "A" should be written instead. This is where we use a default constraint.
The syntax for this is as follows: we write "create table," then the table name, then the column name, followed by the data type, and then we write "default" followed by the value. For instance, I am specifying zero here. If you need to provide a text value, you write the column name, data type, and then the default text value.
This way, when you create a particular table, you can set a default value for it. Today we have covered a total of six constraints. Next, we will talk about joins. Thank you so much for watching Educate Cube. Please like, share, and subscribe to our channel.